I recently purchased a copy of Roman army units the eastern provinces....Raffaele D'amato. On page 46 and on the back cover, he claims that there is a helmet in the private collection of the Archaelogical Museum in Plovdiv

The caption reads that it is a rare helmet.....late 1st C AD.

To me, it looks fake but someone may have other information.

"You have to laugh at life or else what are you going to laugh at?" (Joseph Rosen)